Help with Glue

Tom-D

Tom-D

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Tom-D
Is the new type of glue " Gorilla Glue" as good as the old Uraformaldahide (sp)?

Which is best?
Epoxy, the old formaldehyde, or the new Gorilla glue.

Home builders? what do you use? why?
 
Tom-D said:
what do you use? why?
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At the old day job and side job my go to glue was 3M Contact 10 (yellow). Velcro, vinyl/Naugahyde, felt strips, etc. It also was/is one of the recommended glues for deicer boots. Still use it today. But it won't glue everything.
 
For what application? Different adhesives for different materials and applications. What may be perfect for one thing can be completely wrong for another.

For wood airplane construction I use T-88 epoxy.
 
Gorilla glue expands and spooges out. That's fine on wood or concrete/ceramics but I wouldn't use it on an airplane.
 
Gorilla glue is terrible, and completely worthless. It expands as it cures and destroys anything it is used on. I don't care if they have several types............they don't warn in their original!!

STAY AWAY!!
 
I have two types of GG in the house right now. Their cyanoacrylate ("super" glue) gel is pretty much the same as everyone else's, but comes with a nice brush applicator. The wood glue is, as near as I can tell, virtually identical to Titebond II. I use the wood glue for furniture and other woodworking projects, but I can't think of any use for it on an airplane.
 
Bell206 said:
At the old day job and side job my go to glue was 3M Contact 10 (yellow). Velcro, vinyl/Naugahyde, felt strips, etc. It also was/is one of the recommended glues for deicer boots. Still use it today. But it won't glue everything.
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I should have specified ( Structural glue. ) wood to wood laminating wooden spars.
 
For laminating wood spars, I'd use epoxy. I suppose you could go with urea formaldehyde or resorcinol, but not sure why you would. Certainly not PVA wood glue, but maybe that's just me. You could call Steen and ask what they use for laminated spars.
 
DaleB said:
For laminating wood spars, I'd use epoxy. I suppose you could go with urea formaldehyde or resorcinol, but not sure why you would. Certainly not PVA wood glue, but maybe that's just me. You could call Steen and ask what they use for laminated spars.
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In the past I have found epoxy has a problem with penetration of the wood, and if you clamp it too tightly you squeeze out all the glue, then strength suffers.

I think I'll converse with the Fisher folks see what they recommend to use with their wooden kits.

Thanks for the help.
 
Concurr that the yellowish wood glue is like the old titebond - it's not the expanding stuff (which works well if you clamp sufficiently).

I use the non expanding type on r/c planes where having a wing come apart isn't quite as personal. It's good stuff though.

Agree with above on T-88 but I would ask someone who works on Bellanca Vikings.

Almost no one seems to understand how to use contact cement. I stood biting my tongue last year watching an IA fix some upholstery on my rear bulkhead. Paint both surfaces. Wait until dry - at least 15 minutes. The surface won't really even feel sticky which is why most people don't trust that, and rush the job. At this point you get 1.0 attempts to position things because when the two seemingly dry surfaces touch it's all over. Nothing left to do but press firmly.
I would not use contact cement for structural use.

Unrelated
Years ago my uncle was working a deal on a PT-19. The wings were original The seller said "I can guarantee the wood, but I can't guarantee the glue". He passed on the deal.
 
West System Epoxy - Used in wood laminations in boat building all the time. Lot's of hardener and filler choices too. Think your "squeeze out all the glue" experience might have been the epoxy you were using rather than an overall epoxy issue.
 
Tom-D said:
In the past I have found epoxy has a problem with penetration of the wood, and if you clamp it too tightly you squeeze out all the glue, then strength suffers.

I think I'll converse with the Fisher folks see what they recommend to use with their wooden kits.

Thanks for the help.
Click to expand...


Aha, now we know what the "project" is you were talking about. ;)
 
Isn't there FAA guidance on this?
When to use various glues, and how to apply them?
 
Tom-D said:
Is the new type of glue " Gorilla Glue" as good as the old Uraformaldahide (sp)?

Which is best?
Epoxy, the old formaldehyde, or the new Gorilla glue.

Home builders? what do you use? why?
Click to expand...

I find all these glues have their propose. I like Gorilla Glue, heck I have even used it on one application where I glued iron, to a copper fitting, to plastic for a project I was doing and the strength was steller.

Gorilla glue is also very good for repairing wood siding if you have have an area of decay from water penetration or other small damage.

Use it to glue structural airplane parts, I don't think so.
 
Tom-D said:
In the past I have found epoxy has a problem with penetration of the wood, and if you clamp it too tightly you squeeze out all the glue, then strength suffers.

I think I'll converse with the Fisher folks see what they recommend to use with their wooden kits.

Thanks for the help.
Click to expand...
Yes, like anything else... if you do it, you have to do it right, otherwise you get a bad result. Laminating with resorcinol (for example) required high clamping pressure. Laminating with epoxy does not, and in fact requires just enough pressure for secure assembly so as not to "starve" the joint.

I can save you the call to Fisher... I am building a Celebrity. T-88 epoxy is specified for their kits. I buy it by the quart.
 
Structural glu-lams still appear to use resorcinal glue. Tough and flexible. The flexibility thing should be a consideration.
 
Tom-D said:
I should have specified ( Structural glue. ) wood to wood laminating wooden spars.
Click to expand...
I'd use whatever Steens Aero is currently using for their laminated spars.
 
DaleB said:
Yes, like anything else... if you do it, you have to do it right, otherwise you get a bad result. Laminating with resorcinol (for example) required high clamping pressure. Laminating with epoxy does not, and in fact requires just enough pressure for secure assembly so as not to "starve" the joint.

I can save you the call to Fisher... I am building a Celebrity. T-88 epoxy is specified for their kits. I buy it by the quart.
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I'm not building a fisher product, but I thought they'd know. thanks for that.
I helped build a celebrity years ago, thought they might have changed to something better. (oh well) :)
 
For all...The "wood to wood" spars was just an example of what I'm using the glue for.

I'm just doing the home work for building a small seaplane, uncertain which one yet.
 
Does Gorilla Glue meet AC 43.13?
Help you out a little...

1-4. ADHESIVES. Because of the critical role played by adhesives in aircraft structure, the mechanic must employ only those types of adhesives that meet all of the performance requirements necessary for use in certificated civil aircraft. Use each product strictly in accordance with the aircraft and adhesive manufacturer’s instructions. a. Adhesives acceptable to the FAA can be identified in the following ways: Par 1-2 Page 1-3 AC 43.13-1B CHG 1 9/27/01 (1) Refer to the aircraft maintenance or repair manual for specific instructions on acceptable adhesive selection for use on that type aircraft. (2) Adhesives meeting the requirements of a Military Specification (Mil Spec), Aerospace Material Specification (AMS), or Technical Standard Order (TSO) for wooden aircraft structures are satisfactory providing they are found to be compatible with existing structural materials in the aircraft and the fabrication methods to be used in the repair. b. Common types of adhesives that are or have been used in aircraft structure fall into two general groups: casein and synthetic resins. Adhesive technology continues to evolve, and new types (meeting the requirements of paragraph 1-4a) may become available in the future. (1) Casein adhesive performance is generally considered inferior to other products available today, modern adhesives should be considered first. CAUTION: Casein adhesive deteriorates over the years after exposure to moisture in the air and temperature variations. Some modern adhesives are incompatible with casein adhesive. If a joint that has previously been bonded with casein is to be rebonded with another type adhesive, all traces of the casein must be scraped off before the new adhesive is applied. If any casein adhesive is left, residual alkalinity may cause the new adhesive to fail to cure properly. (2) Synthetic-resin adhesives comprise a broad family which includes plastic resin glue, resorcinol, hot-pressed Phenol, and epoxy. (3) Plastic resin glue (urea-formaldehyde resin glue) has been used in wood aircraft for many years. Caution should be used due to possible rapid deterioration (more rapidly than wood) of plastic resin glue in hot, moist environments and under cyclic swell-shrink stress. For these reasons, urea-formaldehyde should be considered obsolete for all repairs. Any proposed use of this type adhesive should be discussed with the appropriate FAA office prior to using on certificated aircraft. (4) Federal Specification MMM-A181D and Military Specification MIL-A-22397 both describe a required series of tests that verify the chemical and mechanical properties of resorcinol. Resorcinol is the only known adhesive recommended and approved for use in wooden aircraft structure and fully meets necessary strength and durability requirements. Resorcinol adhesive (resorcinol-formaldehyde resin) is a two-part synthetic resin adhesive consisting of resin and a hardener. The appropriate amount of hardener (per manufacturer’s instruction) is added to the resin, and it is stirred until it is uniformly mixed; the adhesive is now ready for immediate use. Quality of fit and proper clamping pressure are both critical to the achievement of full joint strength. The adhesive bond lines must be very thin and uniform in order to achieve full joint strength. CAUTION: Read and observe material safety data. Be sure to follow the manufacturer’s instructions regarding mixing, open assembly and close assembly times, and usable temperature ranges. (5) Phenol-formaldehyde adhesive is commonly used in the manufacturing of aircraft grade plywood. This product is cured at elevated temperature and pressure; therefore, it is not practical for use in structural repair. Page 1-4 Par 1-4 9/8/98 AC 43.13-1B (6) Epoxy adhesives are a two-part synthetic resin product, and are acceptable providing they meet the requirements of paragraph 1-4a. Many new epoxy resin systems appear to have excellent working properties. They have been found to be much less critical of joint quality and clamping pressure. They penetrate well into wood and plywood. However, joint durability in the presence of elevated temperature or moisture is inadequate in many epoxies. The epoxy adhesives generally consist of a resin and a hardener that are mixed together in the proportions specified by the manufacturer. Depending on the type of epoxy, pot life may vary from a few minutes to an hour. Cure times vary between products. CAUTION: Some epoxies may have unacceptable thermal or other hidden characteristics not obvious in a shop test. It is essential that only those products meeting the requirements of paragraph 1-4a be used in aircraft repair. Do not vary the resin-tohardener ratio in an attempt to alter the cure time. Strength, thermal, and chemical resistance will be adversely affected. Read and observe material safety data. Be sure to follow the adhesive manufacturer’s instructions regarding mixing, open and closed curing time, and usable temperature ranges.
 
Gorilla Glue and other similar urethane glues react with residual moisture to cure, and they foam as they react. The foaming creates tiny voids between the components. Boatbuilders don't like that and aircraft builders shouldn't, either.

Still, it's strong stuff. I prefer the Elmer's version of it; it's much cheaper and doesn't foam as much. Sticks to almost anything. For non-porous surfaces you need to wipe the surface with a damp rag first.
 
There was some discussion about Gorilla Glue on (IIRC) the homebuiltairplanes.com forums. Bottom line is that GG (their original expanding foaming polyurethane stuff) is a really bad choice for critical structural applications; it really isn't that strong and tends to be brittle. The one thing it is good for is filling gaps when the joints don't fit well (which is never acceptable in aircraft construction anyway). PVA glues (Elmers, Titebond, etc.) are a lot stronger but require good fitting joints. For aircraft construction the modern choices are epoxy (e.g. T-88 or West System), or you can use the old fashioned choices like resorcinol.
 
Gotta watch epoxies in this app in my opinion. You have heat issues and water issue, make sure you choose appropriately.
 
PaulS said:
Gotta watch epoxies in this app in my opinion. You have heat issues and water issue, make sure you choose appropriately.
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I'm not aware of a water issue with epoxy, but the heat thing is certainly something to consider.
 
PaulS said:
Water can undo certain epoxies, have to be careful.
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That is one advantage of the powder types of glue, they aren't sensitive to moisture.
 
Tom-D said:
That is one advantage of the powder types of glue, they aren't sensitive to moisture.
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You need to be more specific. Some “powder types of glue” are used with water, and are certainly sensitive to moisture.
The way you wrote the quoted text is 100% wrong. I sure hope what you wrote isn’t what you meant to say.
 
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And all this time I thought glue was for sniffing! :cool:
 
Resorcinol requires near perfect joinery, and smooth, (planed, not sanded) mating surfaces, and higher clamping pressure than epoxy.
T-88 is more forgiving of less than perfect joinery, than resorcinal.

I'm not certian, but I don't think the urea formaldehyde glues are "approved" structural adhesives anymore.
 
bluerooster said:
Resorcinol requires near perfect joinery, and smooth, (planed, not sanded) mating surfaces, and higher clamping pressure than epoxy.
T-88 is more forgiving of less than perfect joinery, than resorcinal.

I'm not certian, but I don't think the urea formaldehyde glues are "approved" structural adhesives anymore.
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From AC43-13
(1-4) Plastic resin glue (urea-formalde- hyde resin glue) has been used in wood aircraft for many years. Caution should be used due to possible rapid deterioration (more rapidly than wood) of plastic resin glue in hot, moist envi- ronments and under cyclic swell-shrink stress. For these reasons, urea-formaldehyde should be considered obsolete for all repairs. Any proposed use of this type adhesive should be discussed with the appropriate FAA office prior to using on certificated aircraft.

IOWs get a field approval use it.
 
I'd recommend not putting any urea on an aircraft....or it will deteriorate.;)
 
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Tom-D said:
From AC43-13
(1-4) Plastic resin glue (urea-formalde- hyde resin glue) has been used in wood aircraft for many years. Caution should be used due to possible rapid deterioration (more rapidly than wood) of plastic resin glue in hot, moist envi- ronments and under cyclic swell-shrink stress. For these reasons, urea-formaldehyde should be considered obsolete for all repairs. Any proposed use of this type adhesive should be discussed with the appropriate FAA office prior to using on certificated aircraft.

IOWs get a field approval use it.
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And with the other products out there, I would hazard to guess getting a field approval would be difficult at best.
 
bluerooster said:
And with the other products out there, I would hazard to guess getting a field approval would be difficult at best.
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But here is the reality, Original manufacturer's products don't require any permission to use.

Some times we must decide, what is legal some time isn't safe, what safe some times isn't legal.
But In the E/AB world every thing is legal.
 
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